Revelation 6:4 - Matthew Poole's English Annotations on the Holy Bible

And there went out another horse that was red; signifying blood and slaughter. And power was given to him that sat thereon to take peace from the earth; either to Christ, (as some say), or to those that ruled the affairs of the Roman empire at that time, to disturb the peace of the church. And that they should kill one another: this was a time of much blood. And there was given unto him a great sword; and therefore a sword is given to him that rode upon the this horse. Some think that this period began with Nero, thirty-four years before the other ended (according to what was said before); others make it to begin with Trajan, and to comprehend eighty years, until the time of Commodus; in which time Trajan, and Hadrian, and the three Antoninuses successively ruled the Roman empire: the reigns of Trajan and Hadrian took up near half the time, in which time this prophecy was most eminently fulfilled; for in Trajan's time the Jews rebelling, and killing many subjects of the Roman empire, to the number of twenty-two thousand in one place, and two hundred and forty thousand in another place, themselves were as miserably handled by the Roman forces sent by Trajan and Hadrian, who slew of them (as histories tell us) five hundred and fourscore thousand: nay, the Jews themselves say, they lost double the number of those who came out of Egypt, and more than they lost by Nebuchadnezzar, or by Titus when their city was taken: on the other side the Romans lost very many. Many Christians also were put to death during this period, during which was the third and fourth persecution.